78158986 has 8 divisors (see below), whose sum is σ = 117470340. Its totient is φ = 39002208.

The previous prime is 78158963. The next prime is 78158987. The reversal of 78158986 is 68985187.

It can be written as a sum of positive squares in 2 ways, for example, as 78057225 + 101761 = 8835^2 + 319^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×78158986² = 12217654185096392, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78158987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37371 + ... + 39406.

Almost surely, 2^78158986 is an apocalyptic number.

78158986 is a deficient number, since it is larger than the sum of its proper divisors (39311354).

78158986 is a wasteful number, since it uses less digits than its factorization.

78158986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77288.

The product of its digits is 967680, while the sum is 52.

The square root of 78158986 is about 8840.7570942765. The cubic root of 78158986 is about 427.5559672745. Note that the first 3 decimals are identical.

The spelling of 78158986 in words is "seventy-eight million, one hundred fifty-eight thousand, nine hundred eighty-six".